Dry-cell-sealing device



Sept. 16, 1930. w. F. HENDRY DRY CELL SEALING DEVICE Filed March 9, 1925 NVENTOR mg. M

fi 1K. ATTORNEY Patented Sept. 16, 1930 UNITED STATES PATENT orncr.

WILLIAM F. HENIJRY, OE OSSINING, NEW YORK, ASSIGNOR, BY HESNE ASSIGNMENTS,

1'0 NATIONAL CARBON COMPANY, INC.,

NEW Yon];

OF NEW YORK, N. Y., A CORPORATION OF DRY-CELL-SEALING DEVICE Application filed March a, 1925. Serial No. 14,145.

This invention relates to dry cells, and" more particularly to new and useful improvements in the. sealing of dry cells. In dry batteries of the Le Glanche type 5 it is desirable, as well known, to provide between the depolarizing mix or bobbin and the upper seal, which is usually of pitch, a free space for the gases evolved during the operation of the battery. Otherwise the pressure generated by the gases may burst open the container or the cell and cause the water contained in the mix rapidly to evaporate. Various arrangements have been sug; v gested for this purpose, the simplest of which consists in the provision of a disc of paper or other insulating material provided at a certain distance from the top of the depolarizing mass. In such structures, however, it often happens that after the seal cools and the cell is subjected to more or less.

severe handling, the relatively heavy seal will settle and force the, paper disc flush against the top of the depolarizing agglomerate. This will, of course, destroy the de- .sirable air space. In order to avoid this it has been suggested so to arrange the paper disc, which is made of corrugated cardboard,

that it rests normally on top of the depolarizing mass and provides in its interstices or convolutions the necessary air space. The ob] ect1on to such arrangement '18 that "the paper structur may be crushed by the seal,-

and that its co. struction and insertion into the battery can. is relatively expensive. 7

In order to overcome these difficulties, in accordance with the present, invention-the seal of pitch or ithe like is anchored in the top of the battery can in. a manner to prevent its settling and destroying the gas order to prevent the displacement of' this seal upon cooling, projections are provided in the zinc can which will permanently anchamber. This is accomplished byprovid chor it. It is important that the anchoring.

means do not interfere with the assembly of the battery and particularly with the insert tion or tamping of the depolarizing mixture. I have found that two or threeslight indentations near the top of the zinc can Will serve as a sufiicient anchor without interfering with the assembling operation in any respect.

The drawing illustrates an embodiment of the invention in a dry vcell shown partly in cross section.

The dry cell is of the usualtypein which a zinc electrode 1 surrounds a centrally lo-' cated carbon electrode 2, the space between these electrodes being filled with a mass of depolarizing material '3' which is separated from the zinc electrode by means of a lining 4 of paper or the like. After the insertion of the depolarizing bobbin 3 or the tamping down of the depolarizing mass in the container, the. end of the paper" lining 4 is folded down on top of the depolarizing mass as indicated at 5.- A disc of paper 6 of a sufiiciently large diameter to insure its frictional. en agement with the zinc can 1 is inserted, ut a space 7 is preserved between the top of the depolarizing mass and the paper disc 6. Near the top of the zinc can 1 two or more indentations 8 are made in the can and these indentations serve as an ,material frictionally held at a certain distance from the top of said container, spaced indentations in the zinc container above said disc, and a seal filling the space within the container above said disc v 2. In a dry cell, a zinc container electrode, av carbon electrode centrallyv located therein, depolarizing mass partly filling the annular space in sand container, a disc of insulating material frictionally held at a certain dis.-

tance from the top of said container, spacedindentatlons in the zinc contamer above said disc, said indentations being sufliciently small to allow insertion of the liner Without distortion, and a seal filling the space within the container above said disc.

In testimony whereof, I have signed my name to this specification this 2nd day of March, 1925.

WILLIAM F. HENDRY. 

